US 2010/0036390 A1 discloses a method for delivering a stent to a bifurcation of a vessel. A first guidewire is advanced through a body lumen to a first branch of a vessel bifurcation. A second guidewire is advanced through a body lumen to a second branch of the vessel bifurcation. Moreover, a catheter assembly is advanced to the vessel bifurcation along the first guidewire and the second guidewire, wherein the catheter assembly comprises a catheter shaft defining a first guidewire lumen for receiving the first guidewire and a balloon rotatably disposed about the catheter shaft, wherein the balloon is freely rotatable about the first guidewire. The catheter assembly further comprises a tubular member engaged to an external surface of the balloon, wherein the tubular member defines a second guidewire lumen for receiving the second guidewire, and a stent, wherein the stent is disposed about at least a portion of the balloon and the tubular member and wherein the second guidewire passes through at least one opening defined by the stent. The balloon is rotatable about the first guidewire, in order to allow the stent to be arranged in a desired rotational position. For providing this rotation functionality a technically relatively complex construction of the catheter assembly is required.